Audi's A1 E-Tron plug-in hybrid returns 123 mpg, is handsome and fun to drive, makes no compromises and has a Wankel rotary in the trunk. Unfortunately, there are only a handful in existence, for now.

Ingolstadt, Germany.—Somewhere in the ether of recent history, during the hybrid automobile's baby steps of development, a jaded marketing man and a frustrated middle manager met in a florescent-lighted, windowless room and decided fun should be sacrificed at the altar of efficiency. On that day, the hybrid car was made an appliance. Of course, the idea that fun and efficiency cannot happily coexist is just plain silly. Cars like the Honda CR-Z and Chevy Volt are slowly chipping away at that notion, but the Audi A1 E-Tron is a prototype car that completely demolishes it. Its major flaw is that it's not for sale, at least for now.

The Specs

Like other hybrid cars on the market today, the A1 E-Tron begins with a production-based frame and chassis. The premium three-door hatchback sold as the A1 in Europe utilizes a strut front suspension, torsion-beam rear suspension and four-wheel disc brakes. From there, the A1 E-Tron goes in a completely different direction. The peppy inline Four from the production car is tossed out for a modular power pack featuring a direct-drive, asynchronous electric traction motor with a continuous output of 60 hp and 111 lb-ft of torque; peak output gets up to 100 hp and 177 lb-ft of torque. The compact design means it fits ahead of the front wheels and down low in the chassis. This is the only source of motivation for the A1 E-Tron. Powering this electric motor to a range of 35 miles is a T-shaped lithium-ion battery pack living under the rear seats and in the vacant exhaust tunnel. The famous four-ring logo in the grille cleverly opens out to reveal an integrated plug-in port for charging at up to 400 volts in 2 hours.

Things get interesting when you take a look at what lies below the nondescript, standard-height rear-load floor: a single-rotor, constant-speed Wankel rotary engine. The 254-cc engine is the car's gasoline-powered range extender, and its sole purpose is to quietly and smoothly run a 15-kilowatt-hour (kwh) generator. Electricity flows to the 12-kwh battery and electric motor up front, and it's so quiet that you never even know that it's happening.

Wankels have always been something of a novelty, with only Mazda using them for the past few decades. Their finicky seals, low torque and fuel-hungry nature often outweighed their benefit of light weight and extremely compact dimensions. As a generator engine, however, they are a different proposition. Because there are no reciprocating pistons, the engines are incredibly smooth, nearly vibration-free, and when optimized for operation at a single rpm, can be made extremely efficient, all attributes at home in an EREV.

Audi has also applied other solutions it sees as key to the future success of electrified motoring. Banished is the traditional air-conditioning and heating system; in its place is a high-efficiency heat pump that keeps the cabin comfortable. Carbon fiber has been used in the roof to lower weight; electrically boosted power steering and power brakes reduce energy requirements.

The end result is simultaneously more and less than you'd expect: less in that nothing indicates this car is something special save the badging and the unique instrument cluster—everything else looks just like a regular A1. Same cargo capacities, similar acceleration at 10.2 s 0—62 mph, a respectable 80-mph top speed. And that's why it's more: It's a forward-looking techno-wonder prototype, and it feels like it just rolled off a production line without fanfare.

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The Drive

The walkup to the A1 E-Tron is unremarkable. Aside from show-car carbon-fiber wheel covers and "E-tron" badging, it looks like any A1 skipping across Germany. When the car is on, it whirs and whispers, but you have to be paying attention. Inside, the cabin is familiar A1 territory: common shapes and materials built to exacting Audi standards. The instrument panel and shift lever are something new. A steely LCD gauge interface shows a diagram of the car, basic status details and all the pertinent information. The shifter gives the standard PRND, but there's a funny A Off where Low should be.

"A Off" defeats a system called Audi Economy Assist, a route planner designed to maximize fuel economy by delivering the car to its destination as cheaply as possible—with a depleted battery and minimum range-extender run time. First, the driver enters the destination into the navigation system. From there, the software crunches the traffic patterns and elevation changes on the planned route to determine how often to run the gas engine. The system then seamlessly carries out those operations unbeknownst to the driver, who travels efficiently carefree.

We did not have a chance to sample the course-planning system because we were only allowed to drive the car on a close course. But that's okay, since we switched to A Off and found that, essentially, that's the hooligan mode. Here, the range extender provides additional power to the e-motor. Peak output is 177 lb-ft of torque and 100 hp of power at a standstill. This thing moves. The luscious instant-on torque of electric motoring is smoothly delivered to the front wheels in a way you'd expect from an Audi. The electrically assisted power steering maintains precise feedback and builds predictably through understeer. Because all of the weight centers in the car are low in the chassis, the car corners even better than the regular A1. Switchbacks and tight hairpin corners are exhilarating, and power out of the corner comes with a delightful, Jetsons-esque whir.

The cars' paddle shifters are repurposed. Rather than shift the nonexistent transmission, pulling the plus or minus paddles adjusts the behavior of the regenerative braking system. The plus paddle engages greater motor drag, increased braking energy capture, so the car slows more dramatically without applying the hydraulic brakes. Toggling the minus paddle lets the car coast freely.

Those paddles are a cool way to adjust the driving behavior. But no matter the mode, the A1 E-Tron is a genuinely fun car to drive: less science experiment and more hot hatch, like a GTI. While we were sawing away at a cone course, the rotary engine kicked on. We wouldn't have noticed or cared except for the dash indication. Between a fully charged battery and the 3-gallon fuel tank, the A1 E-tron has a maximum range of about 155 miles, which Audi considers appropriate for a "megacity car." After that, the car must be recharged and refueled before additional travel. Its combined fuel economy has been measured at nearly 123 mpg, a figure we'd be pleased to test for ourselves. This is a hybrid done right, to the point where the range and economy are incredible, but it's the driving experience that we would rather talk about.

The Bottom Line

Audi has been quietly but ferociously working on their vehicle-electrification future. This A1 E-Tron provides a shockingly polished taste of just how good EREV hybrids can be when fresh thinking is brought to the table. It's nimble, satisfying and economical to drive. It's not just a really good hybrid, it's a really good car that happens to be a hybrid. If this is the future of hybrid vehicles, even enthusiasts can welcome them with open arms.

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